Piano abstract and assembly



Feb. 17, 1959 M. D. CORWIN 2,873,633

PIANO ABSTRACT AND ASSEMBLY Filed Jan. 27, 1955 INVENTOR. Meier-0N aCak'wnv,

BY allwnw A'r TORN E'YS.

United States Patent PIANO ABSTRACT AND ASSEMBLY Merton D. Col-win,Cincinnati, Ohio, assignor to The Baldwin Piano Company, Cincinnati,Ohio, a corporation of Ohio Application January 27, 1955, Serial No.484,382

2 Claims. (Cl. 84-243) In United States Patent 2,548,890, Armand F.Knoblaugh described a type of drop action for small upright pianoscharacterized by a new type of abstract assembly. In the action, thewippens were located substantially below the level of the key bed andkey board, and motion was transmitted from the keys to the wippens bymeans of elongated abstracts of rod-like form. The abstracts were bentover at their upper ends to form ledges or fingers overlying the capstanscrews of the keys; and at their lower ends they were either flattenedand provided with pins for pivotal connection to the wippens, orprovided with axially extending, transverse, loop-like wire members forthe same purpose.

The abstracts were guided in holes in a member removably mounted to thekey frame or key bed, the holes being of a size to accept the bodies ofthe abstracts, and being connected to the edge of the guide member byslots of a lesser transverse dimension. It was possible to remove anabstract by disconnecting it from the wippen, pulling it upwardlythrough the guide member until its flattened portion or its wire loopbegan to enter the hole, turning it through about 90, and withdrawing itfrom the guide member laterally through the slot. It was also possible,by disconnecting the guide member from the key bed, to remove the wholeaction and abstract assembly from the instrument. When the abstractswere in use, their pivotal connection with the wippens kept their ledgesor fingers in alignment over the keys.

A primary object of this invention is to provide improvements in dropactions of this type, and particularly in the abstracts thereof.

It is an object of the invention to provide piano abstracts andassemblies at substantially reduced cost.

It is an object of the invention to provide abstracts with enhancedstrength in the pin area.

It is an object of the invention to provide abstracts which may beeconomically mass produced by die casting.

It is an object of the invention to provide abstracts which are moreeasily removed from the guide member, inasmuch as they do not requirethe rotary motion hereinabove described.

These and other objects of the invention, which will be set forthhereinafter or will be clear to the skilled worker in the art uponreading these specifications, are accomplished by that construction andarrangement of parts of which an exemplary embodiment will now bedescribed. Reference is made to the accompanying drawings, wherein:

Fig. 1 is a vertical sectional view showing in assembly elements of theaction, the abstract and a coacting key.

Fig. 2 is a partial perspective view showing the coaction of an abstractand the guiding means.

Fig. 3 is a partial perspective view of the end of a wippen.

Fig. 4 is a partial elevational view showing the lower end of theabstract and the forward end of the wippen in pivotal engagement.

2,873,638 Patented Feb. 17, 1959 Fig. 5 is a partial plan view of amodified guiding means.

In Fig. 1 an action is indicated generally at 1, mounted upon actionbrackets, one of which is shown at 2. A string of the instrument isshown at 3. The action brackets are normally mounted to the plate of thepiano, not shown. The elements of the action are or may be conventional,and require no description here. The action, however, comprises a seriesof wippens, one of which is shown at 4. The wippens are pivoted, as at5, to elements 6 affixed to a rail 7 in the action.

The key bed of the instrument is partially shown in section at 8. On thekey bed there is a key fram 8a upon which is mounted a plurality of keysin the usual fashion, one of which is partially shown at 9. The rearends of the keys preferably bear conventional capstan screws, as at 10.I

An abstract 11 is pivotally connected as at 12 to the forward end of thewippen 4. The abstract is guided by a guide means 13 preferably attachedto the key bed 8, as shown. The upper end of the abstract has anangularly related ledge or finger 14 overlying the capstan screw 10. Itwill be clear from Fig. 1 how an upward motion of the rear end of thekey 9 is transmitted by the abstract to the Wippen 4.

The guiding means for the abstracts is more clearly shown in Fig. 2 ascomprising a plate of suitable substance, preferably of metal. Forrigidity the plate may be provided with a flange 15 at its forward edge.The plate is provided with a series of holes 16 to accept the bodies ofthe abstracts in sliding relationship. These holes are connected withthe rear edge of the plate by slots 17 having a width less than thediameters of the holes. Where the pIate of the guide member 13 is ofmetal, the holes and slots may be lined with a quieting material such asthe felt strip 18. The plate will be provided with suitable holes 19 sothat it may be attached to the key bed with suitable screws or bolts.

In Fig. 5 a guiding means is shown in which like parts have been givenlike index numerals. Instead of sounddeadening material applied as shownin Fig. 2, a strip of felt 33 may be adhesively applied to the upper orlower face of the plate 13. This strip will be characterized by holes 34overlying the plate holes 16, and by slits 35 overlying the slots 17,the slits connecting the holes to the outer edge of the felt strip. Theholes 34 are somewhat smaller in diameter than the holes 16 so that thebodies of the abstracts are prevented from contacting the metal plate13. The felt body is sufliciently flexible to permit the withdrawal ofthe flattened portions of the abstracts through the slots 17 and slits35 as hereinafter more fully described.

The guiding means may be mounted either to the key frame or to the keybed (preferably the latter, as shown); and if desired a strip of felt 36in Fig. 1 may be interposed between the plate 13 and the surface towhich it is attached.

The guiding means may be a single plate substantially the length of thekey bed or a plurality of plates in end-to-end relationship, whicheveris more convenient. Although the guiding means could be otherwisemounted, attaching it to the key bed takes care of reasonabledimensional inequalities between different instruments. If it is desiredto remove the action from the instrument, the guide means may bedisconnected from the key bed and tied back against the action rail 20,whereupon the action may be taken out of the instrument by disconnectingthe action brackets 2. The abstracts, it will be noted, have nomechanical interlock with the keys.

The length of the abstracts may be varied as desired depending upon thedimensions of the instrument and the position of the action with respectto the key bed.

'The abstracts are made of suitably rigid material preferably of metaland are so designed that they may be easily and cheaply mass produced bydie casting operations. They comprise an elongated cylindrical body 11of appropriate length surmounted at the top by the :angularly relatedledge or finger 14 which is flattened and preferably has a width greaterthan the diameter the light of the approximate angularity of the body 11to the vertical in the finished instrument. The juncture of the ledgeand the body may be rigidified as by a fillet 21 if desired. Asound-deadening material, such as felt or rubber, is useful where theledge is to be contacted by the capstan screw; and this is convenientlyapplied in the form of a felt pad 22 beneath the ledge and held in placeby adhesive. A locating shoulder for the sound-deadening material may beformed on the ledge at the position 23.

The lower end of the abstract is bifurcated to have a fork shape, as at2 i with interspaced tines 25 and 26. It will be noted that the width ofthe fork is substantially greater than the diameter of the cylindricalbody 111; and the fork may be made of any desired dimensions foradequate strength.

Adjacent the fork and, in eifect, connecting it with the body, there isa flat 27. This flat has a thickness less than the effective width ofthe slots 117 in the guide member 13. It will be apparent from Fig. 2that the abstract may be disengaged from the guiding means by merelydrawing it upwardly until the flat 27 may be withdrawn rearwardlythrough the slot 17. In doing so, it is not necessary to rotate theabstract since the fiat will be found in alignment with the slot whenthe abstract is merely moved axially.

The wippen 4, as shown in Fig. 3, will normally have a reduced frontportion 28. This contains an opening 29 for the pivot pin of theabstract. The opening is bushed with felt or other suitable resilientmaterial and is so formed as to have a slot-like opening below, as at30. The tines 25 and 26 of the abstract are pinned,

as at 31. To accomplish this, the tines are drilled with suitably sizedholes adjacent their lower ends and a wire of desired strength andsubstance is passed through the holes. The wire may be fastenedpermanently in position in any suitable way, as by flattening its endsbeyond the tines. This is indicated at 32. When the abstract isassembled to the wippen, the wire or pin 31 is merely passed through theslot 30 in the wippen end.

To do this, the felt or other bushing has to be compressed.

d The pin will snap into position under the application of force, andthe resistance of the bushing will be suflicient to overcome the weightand inertia of the abstract so as to prevent unintentionaldisengagement.

Since the fork 24 may be made of any size, it is not necessary in allinstances to reduce the end of the wippen, as at 28, where thedimensions of the instrument permit. An individual abstract is readilyremovable at any time from the instrument by disengaging it from itswippen, then drawing it upwardly and disengaging it from the guidingmember, as hereinabove described.

Modifications may be made in the invention without departing from thespirit of it. The invention having been described in an exemplaryembodiment, what is claimed as new and desired to be secured by LettersPatent is:

1. An abstract for a musical instrument consisting of a one-piece diecast metallic element having an elongated substantially cylindrical bodyterminating at its upper end in an angularly related ledge, saidcylindrical body terminating at its lower end in a fiat portion oflesser thickness than said body and a fork at the lower end of said flatportion, said flat portion and said fork extending in prolongation ofsaid cylindrical body with the plane of said fork lying at substantiallyright angles with respect to the direction of extension of said ledge.

2. An abstract for a musical instrument consisting of a unitary die castmetalic element having an elongated substantially cylindrical bodyterminating at its upper end in an angularly related ledge having awidth substantially greater than the diameter of said cylindrical bodyand a flat undersurface capable of receiving a pad, said cylindricalbody terminating at its lower end in a flat portion of lesser thicknessthan said body and a fork at the lower end of said flat portion, saidflat portion and said fork extending in prolongation of said cylindricalbody with the plane of said fiat portion lying in substantial alignmentwith the direction of extension of said ledge and at substantially rightangles to the plane of said fork.

References (Iited in the file of this patent UNITED STATES PATENTSFranklin June 30, 1953

